America's agricultural landscape is now 48 times more toxic to honeybees, and likely other insects, than it was 25 years ago, almost entirely due to widespread use of so-called neonicotinoid pesticides, according to a new study published this month in the journal PLOS One. From a report: This enormous rise in toxicity matches the sharp declines in bees, butterflies, and other pollinators as well as birds, says co-author Kendra Klein, senior staff scientist at Friends of the Earth US. "This is the second Silent Spring. Neonics are like a new DDT, except they are a thousand times more toxic to bees than DDT was," Klein says in an interview. Using a new tool that measures toxicity to honey bees, the length of time a pesticide remains toxic, and the amount used in a year, Klein and researchers from three other institutions determined that the new generation of pesticides has made agriculture far more toxic to insects. Honey bees are used as a proxy for all insects. The U.S. Environmental Protection Agency does the same thing when requiring toxicity data for pesticide registration purposes, she explained.

The study found that neonics accounted for 92 percent of this increased toxicity. Neonics are not only incredibly toxic to honeybees, they can remain toxic for more than 1,000 days in the environment, said Klein. "The good news is that we don't need neonics," she says. "We have four decades of research and evidence that agroecological farming methods can grow our food without decimating pollinators." "It's stunning. This study reveals the buildup of toxic neonics in the environment, which can explain why insect populations have declined," says Steve Holmer of American Bird Conservancy. As insects have declined, the numbers of insect-eating birds have plummeted in recent decades. There's also been a widespread decline in nearly all bird species, Holmer said. "Every bird needs to eat insects at some point in their life cycle."

The Boston Public School District held a contest to determine the best solution for busing around 25,000 students to school every day. The winning algorithm improved the efficiency of the routes in 30 minutes. From a report: In 2017, the district was facing serious challenges. On a per-pupil basis, Boston Public Schools had the highest transportation costs in the country, around $2,000 per student per year, representing 10% of the district's budget. The schools dealt with rising costs each year, despite declining ridership. The on-time performance rate of their buses was also well below that of other large districts. With no clear vendor to turn to with this problem, BPS instead sought out experts, hosting a competition where researchers could experiment with anonymized BPS data sets to create efficient routes and optimal start times for each school.

"To put it simply, we wanted a solution that worked," said Will Eger, the BPS senior strategic projects manager. "There are lots of quirks in this transportation situation, and we wanted something that could address the vast majority of those issues while also being highly efficient, something that could run overnight at least." Those quirks represent millions of decision variables that affect any solution, including varying road widths, differing bus infrastructures (for example, the presence of wheelchair lifts or child safety restraint seats), students who require the same bus driver every year, students who have monitors, and students who have been in fights and, therefore, need to be on different buses. It also includes the roughly 5,000 students who have a special need that requires door-to-door pick up and drop off (sometimes to non-BPS schools, as the city provides yellow bus service to students who attend charter and private schools within Boston, and to special education facilities outside the city).

Considering all those possibilities creates a "number of solutions so large that you can't even enumerate it," said Arthur Delarue, a PhD candidate who worked with the team from the MIT Operations Research Center whose algorithm won the competition. The team spent hundreds of hours devising a solution to what Delarue called a "bold and unusual" challenge. Their solution replaced what had before been an incredibly laborious process, one that took ten school system routers thousands of hours to create custom routes for each child and school. Those employees still work with BPS, tracking routes that struggle with on-time performance, and managing route guidance for drivers (Google Maps isn't sufficient since it's built for cars, and 70-passenger buses can't, for example, easily make u-turns). But now, the MIT algorithm routes the entire system at once, providing a base for the human routers to tweak.

An anonymous reader quotes a report from National Geographic: A fungus that has wreaked havoc on banana plantations in the Eastern Hemisphere has, despite years of preventative efforts, arrived in the Americas. ICA, the Colombian agriculture and livestock authority, confirmed on Thursday that laboratory tests have positively identified the presence of so-called Panama disease Tropical Race 4 on banana farms in the Caribbean coastal region. The announcement was accompanied by a declaration of a national state of emergency. The discovery of the fungus represents a potential impending disaster for bananas as both a food source and an export commodity. Panama disease Tropical Race 4 -- or TR4 -- is an infection of the banana plant by a fungus of the genus Fusarium. Although bananas produced in infected soil are not unsafe for humans, infected plants eventually stop bearing fruit. First identified in Taiwanese soil samples in the early 1990s, the destructive fungus remained long confined to Southeast Asia and Australia, until its presence was confirmed in both the Middle East and Africa in 2013. Experts feared an eventual appearance in Latin America, the epicenter of the global banana export industry. No known fungicide or biocontrol measure has proven effective against TR4.

A nuclear power system that could one day provide juice to colonies on Mars is closer to being ready than previously expected. According to project team members, the Kilopower experiment fission reactor could be ready for its first in-space trial by 2022. Space.com reports: A flight test is the next big step for the Kilopower experimental fission reactor, which aced a series of critical ground tests from November 2017 through March 2018. No off-Earth demonstration is on the books yet, but Kilopower should be ready to go by 2022 or so if need be, said Patrick McClure, Kilopower project lead at the Department of Energy's (DOE) Los Alamos National Laboratory in New Mexico.

"I think we could do this in three years and be ready for flight," McClure said late last month during a presentation with NASA's Future In-Space Operations working group. "I think three years is a very doable time frame," he added, stressing that this is his opinion, not necessarily that of NASA, which is developing the Kilopower project along with the DOE. As its name suggests, the Kilopower reactor is designed to generate at least 1 kilowatt of electrical power (1 kWe). Its output is scalable up to about 10 kWe, and it can operate for about 15 years, McClure said. So, four scaled-up Kilopower reactors could meet the energy needs of NASA explorers, with a fifth reactor likely landed to provide a spare.

An anonymous reader quotes a report from Wired: Amid unrelenting chaos and violence, scientists and doctors in the Democratic Republic of Congo have been running a clinical trial of new drugs to try to combat a year-long Ebola outbreak. On Monday, the trial's cosponsors at the World Health Organization and the National Institutes of Health announced that two of the experimental treatments appear to dramatically boost survival rates. Starting last November, patients in four treatment centers in the country's east, where the outbreak is at its worst, were randomly assigned to receive one of four investigational therapies -- either an antiviral drug called remdesivir or one of three drugs that use monoclonal antibodies. Scientists concocted these big, Y-shaped proteins to recognize the specific shapes of invading bacteria and viruses and then recruit immune cells to attack those pathogens. One of these, a drug called ZMapp, is currently considered the standard of care during Ebola outbreaks. It had been tested and used during the devastating Ebola epidemic in West Africa in 2014, and the goal was to see if those other drugs could outperform it. But preliminary data from the first 681 patients (out of a planned 725) showed such strong results that the trial has now been stopped.

Patients receiving Zmapp in the four trial centers experienced an overall mortality rate of 49 percent, according to Anthony Fauci, director of the NIH's National Institute of Allergy and Infectious Diseases. (Mortality rates are in excess of 75 percent for infected individuals who don't seek any form of treatment.) The monoclonal antibody cocktail produced by a company called Regeneron Pharmaceuticals had the biggest impact on lowering death rates, down to 29 percent, while NIAID's monoclonal antibody, called mAb114, had a mortality rate of 34 percent. The results were most striking for patients who received treatments soon after becoming sick, when their viral loads were still low -- death rates dropped to 11 percent with mAb114 and just 6 percent with Regeneron's drug, compared with 24 percent with ZMapp and 33 percent with Remdesivir.

A Tesla driver figured out a way to implant the RFID tag from her Model 3's keycard into her forearm. Now, all she needs to do to unlock and turn on her car is to hold her forearm near the console -- no physical key fob or smartphone required. The Verge reports: Amie DD is a software engineer and self-described "maker of things." In a video, she explained that she had implanted an RFID tag in her arm years ago, which she had used to open her home's front door and to send a smartphone's browser to her personal website. When she preordered her Model 3, she realized that she could probably do something similar with the keycard. She didn't have any luck transferring the software to her existing chip, so she decided to extract the card's chip and implant that into her arm. To do that, she dissolved the card using acetone, and had it encased in a biopolymer. From there, she went to a body-modification studio to have the chip (about the size of a Lego mini-figure) implanted into her forearm. In another video (warning, there's some blood), she shows off the implantation. She also documented her process on Hackaday. She told The Verge that the chip does work, but the range from her arm to the console "isn't the greatest." It's only about an inch, but she's hoping that it'll improve as the swelling of her arm goes down.

pgmrdlm shares a report from StudyFinds: So many people, especially young people and teenagers, spend a significant period of time each day staring at a screen of some kind, whether that be a computer, smartphone, tablet, or the regular old TV. Now, a new study is warning parents that all that screen time may be behind a stunning rise in children who need prescription glasses. According to the report released by United Kingdom-based eye care company Scrivens Opticians, the percentage of 13-16 year olds in the U.K. who need glasses has nearly doubled over the past seven years -- from 20% in 2012 to 35% in 2018. Two-thirds of those teens were diagnosed as being myopic, or short-sighted. Researchers theorize that this significant increase in eye problems among young people is likely linked to excessive time spent staring at screens, which can lead to eye strain, shortsightedness, and blurred vision. In fact, the study also found that the average 13-16 year old spends around 26 hours per week staring at a smartphone, playing video games, or watching TV.

We've long been obsessed with the super-elderly. How do some people make it to 100 or even 110 years old? Why do some regions -- say, Sardinia, Italy, or Okinawa, Japan -- produce dozens of these "supercentenarians" while other regions produce none? Is it genetics? Diet? Environmental factors? Long walks at dawn? From a report: A new working paper released on bioRxiv, the open access site for prepublication biology papers, appears to have cleared up the mystery once and for all: It's none of the above. Instead, it looks like the majority of the supercentenarians (people who've reached the age of 110) in the United States are engaged in -- intentional or unintentional -- exaggeration. The paper, by Saul Justin Newman of the Biological Data Science Institute at Australian National University, looked at something we often don't give a second thought to: the state of official record-keeping. Across the United States, the state recording of vital information -- that is, reliable, accurate state record-keeping surrounding new births -- was introduced in different states at different times. A century ago, many states didn't have very good record-keeping in place. But that changed gradually over time in different places.

Newman looks at the introduction of birth certificates in various states and finds that "the state-specific introduction of birth certificates is associated with a 69-82% fall in the number of supercentenarian records." In other words, as soon as a state starts keeping good records of when people are born, there's a 69 to 82 percent fall in the number of people who live to the age of 110. That suggests that of every 10 supposed supercentenarians, seven or eight of them are actually younger than that, but we just don't know it because of poor record-keeping.

The Trump administration on Monday announced that it would change the way the Endangered Species Act is applied, significantly weakening the nation's bedrock conservation law credited with rescuing the bald eagle [Editor's note: the link may be paywalled; alternative source], the grizzly bear and the American alligator from extinction. From a report: The changes will make it harder to consider the effects of climate change on wildlife when deciding whether a given species warrants protection. They would most likely shrink critical habitats and, for the first time, would allow economic assessments to be conducted when making determinations. The rules also make it easier to remove a species from the endangered species list and weaken protections for threatened species, a designation that means they are at risk of becoming endangered. Overall, the new rules would very likely clear the way for new mining, oil and gas drilling, and development in areas where protected species live.

Interior Secretary David Bernhardt said the changes would modernize the Endangered Species Act and increase transparency in its application. "The act's effectiveness rests on clear, consistent and efficient implementation," he said in a statement Monday. Commerce Secretary Wilbur Ross said in a statement the revisions "fit squarely within the president's mandate of easing the regulatory burden on the American public, without sacrificing our species' protection and recovery goals." The new rules are expected to appear in the Federal Register this week and will go into effect 30 days after that.

"Despite decades of research, there's no viable roadmap for how to scale quantum cryptography to secure real-world data and communications for the masses," according to IEEE Spectrum.

Wave723 shares their report: A handful of companies now operate or pay for access to networks secured using quantum cryptography in the United States, China, Austria, and Japan. According to a recent industry report, six startups plus Toshiba are leading efforts to provide quantum cryptography to governments, large companies (including banks and financial institutions), and small to medium enterprises. But these early customers may never provide enough demand for these services to scale...

From a practical standpoint, then, it doesn't appear that quantum cryptography will be anything more than a physically elaborate and costly -- and, for many applications, largely ignorable -- method of securely delivering cryptographic keys anytime soon. This is in part because traditional cryptography, relying as it does on existing computer networks and hardware, costs very little to implement. Whereas quantum crypto requires an entirely new infrastructure of delicate single-photon detectors and sources, and dedicated fiber optic lines. So its high price tag must be offset by a proven security benefit it could somehow deliver -- a benefit that has remained theoretical at best.
Though it was supposed to replace mathematical cryptography, "Math may get the last laugh," the article explains. "An emerging subfield of mathematics with the somewhat misleading name 'post-quantum cryptography' now appears better situated to deliver robust and broadly scalable cryptosystems that could withstand attacks from quantum computers." They quote the security engineer at a New York cybersecurity firm who says quantum cryptography "seems like a solution to a problem that we don't really have."

The article ends by suggesting that research may ultimately be applicable to quantum computers -- which could then be used to defeat math-based cryptography. But riffing on the article's title, sjames (Slashdot reader #1,099) quips that instead of giving quantum cryptography a reboot, maybe it just needs the boot.

A Texas-based, father/son team raised $4.5 million in seed funding to build "a remarkable electric motor technology," reports New Atlas.

Long-time Slashdot reader Namarrgon writes: Linear Labs' impressive new circumferential flux motor design (video) uses four rotors [where other motors typically run one or two] and a software-reconfigurable, multi-coil stator, enclosed in a 3D magnetic "torque tunnel" to maximize efficiency even at high speeds. The stator can be configured on the fly by regrouping coils to use a variable number of overlapping phases simultaneously, producing full torque smoothly at low rpms without torque pulsing, or changing speeds with no change to frequency, current, or voltage, like an electronic transmission. An innovative approach to field weakening by gradually misaligning permanent magnets allows efficiencies to actually climb as speeds increase.

These features produce a highly compact motor with two to five times the torque density, at least three times the power density and at least twice the total output of any conventional permanent magnet motor of the same size. This also eliminates the need for gearing in many applications, reducing costs and weight while gaining 10-20% more range from a given battery pack.

Linear Labs has received 21 patents so far, with another 29 pending, and their prototypes have been verified by independent expert tests. Recently they received $4.5 million in seed funding, and are planning to build them into car and scooter prototypes over the next couple of years.

"Hearing loss in middle age is associated with higher odds of cognitive decline and dementia in later years," reports Reuters, citing a large study in Taiwan. Researchers tracked more than 16,000 men and women and found that a new diagnosis of hearing loss between ages 45 and 65 more than doubled the odds of a dementia diagnosis in the next dozen years. Even mild levels of hearing loss could be a risk factor, so hearing protection, screening and hearing aids may be important means of reducing cognitive risk as well, the study team writes in JAMA Network Open.

"Hearing loss is a potential reversible risk factor for dementia, including Alzheimer's disease," said senior study author Charles Tzu-Chi Lee of National Taiwan Normal University in Taipei.

Past research suggests that about two thirds of the risk for dementia is hereditary or genetic, which means about one third of the risk is from things that are modifiable, Lee noted. Among modifiable risk factors, hearing loss accounts for about 9% of dementia risk, a greater proportion than factors like hypertension, obesity, depression, diabetes and smoking. "The early identification of hearing loss ... and successful hearing rehabilitation can mitigate the negative effects of hearing loss," Lee told Reuters Health by email.

As of Tuesday the Curiosity rover has been on Mars for over seven years, and this week NASA shared an interactive 360-degree panorama of the planet's Teal Ridge.

Digital Trends provides this update: Curiosity is halfway along its path through a region called the "clay-bearing unit" because the area has a high level of clay minerals. Clay minerals are of particular interest to scientists because they form in the presence of water, suggesting that there used to be water in this location thousands of years ago... The engineers estimate that the rover still has several years of power left in its nuclear power system, and will be able to continue operating beyond that with careful power budgeting.
"This nuclear power source, by the way, means that Curiosity is better equipped to handle monster Mars dust storms, such as the one that killed NASA's solar-powered Opportunity rover last year," reports Space.com, sharing more highlights from the years since Curiosity's touchdown: [T]he rover quickly determined that the 96-mile-wide (154 kilometers) crater had hosted a lake-and-stream system in the ancient past. And further observations suggested that this environment was habitable for long stretches, perhaps hundreds of millions of years at a time. Curiosity has also detected several surges of methane in Gale Crater's air...

Curiosity may well live to welcome two more rovers to the Red Planet: NASA's Mars 2020 rover, whose design is based heavily on that of Curiosity, and the European-Russian ExoMars rover are both scheduled to touch down in February 2021.
Tablizer (Slashdot reader #95,088) shares a recent triumph that one NASA official says "represents months and months of work by our team." When an electric motor stalled inside Curiosity's drill, it left the rover unable to reliably extend and retract its drill bit. With the drill feed mechanism no longer reliably working, managers decided to keep the drill bit in its extended position. That raised concerns over the stability of the drill while in use because the prong-like extensions on each side of the bit will no longer be in contact with the rock. "We had to do a big pivot in the mission thinking about how we could drill without the feed motor," said Ashwin Vasavada, the Curiosity mission's project scientist at JPL, in a presentation to the Mars Exploration Program Analysis Group in April.

Controllers devised a way to use force applied by the robotic arm to null out forces generated by the drill, a role the arm was never designed to fill. Engineers used a replica of the Curiosity rover at JPL's "Mars Yard" to test out the new drilling techniques, and the rover drilled a test hole in a rock on Mars in February. That test did not produce a scientifically useful rock sample -- it used only the drill's rotary mechanism, not its hammer-like percussion capability -- but yielded important data for engineers to continue refining the updated drilling technique.
And thanks to this ongoing improvisation, the Curiosity mission's project scientist says, "We now have a key sample we might have never gotten."

A new study published in the American Heart Association journal Circulation: Cardiovascular Imaging found that blood pressure can be measured accurately by taking a quick video selfie. An anonymous reader quotes this announcement from the University of Toronto: Kang Lee, a professor of applied psychology and human development at the Ontario Institute for Studies in Education and Canada Research Chair in developmental neuroscience, was the lead author of the study... Using a technology co-discovered by Lee and his postdoctoral researcher Paul Zheng called transdermal optical imaging, researchers measured the blood pressure of 1,328 Canadian and Chinese adults by capturing two-minute videos of their faces on an iPhone. Results were compared to standard devices used to measure blood pressure. The researchers found they were able to measure three types of blood pressure with 95 to 96 per cent accuracy.
Lee co-founded a company to turn their technology into a smartphone app (named Anura) that reports stress-level measurements and resting heart rate from a 30-second video of your face -- with plans to release a new version also returning blood pressure results sometime this fall in China.

The university also notes that the researchers now hope to extend their technology so it can measure blood-gluclose levels and cholesterol.

An anonymous reader quotes a report from The New York Times, written by philosophy professor Lori Gruen: Sarah, who could have been deemed the world's smartest chimp, was brought to the United States from Africa as an infant to work with David and Ann Premack in a series of experiments designed to find out what chimpanzees might think. In order to determine what, if anything, might be on Sarah's mind, she was one of the first chimpanzees to be taught a human language. The Premacks taught her to use plastic magnetic tokens that varied in size and color to represent words. She formed sentences by placing the tokens in a vertical line. Ann Premack noted that her earliest words named "various interesting fruits," so that Sarah "could both solve her problem and eat it."

Sarah's career established that not only do chimpanzees have complex thoughts, but also distinct personalities with strong preferences and prejudices. But this is just part of her remarkable life story. As she grew older she helped a diabetic chimpanzee named Abby, who she was living with, remember to get her medication. She was a loving, yet stern, aunt-like figure to a pair of young chimpanzees, Harper and Emma, and she helped Henry, a male chimpanzee who came from a situation of terrible abuse, get along with other chimpanzees. Since the time that Sarah was thought to have established that chimpanzees know what others might want or need, a growing number of investigators have tried to figure out if other animals have a theory of mind. Though there have always been skeptics, studies have suggested that crows, jays, ravens, other apes, monkeys, and maybe dogs, may know what others are thinking. In social animals, being able to glean what others might be thinking is a good strategy for getting along. For chimpanzees living in sanctuaries, it can facilitate care.

An amateur astronomer in Texas captured a rare sight earlier this week when an apparent meteor slammed into Jupiter's thick upper atmosphere. Gizmodo reports: On Wednesday, amateur astronomer Ethan Chappel was on the lookout for Perseid meteors, reports ScienceAlert. But his telescope was trained on Jupiter with the camera running. Later, after feeding the data into a software program designed to detect impact flashes, Chappel was alerted to the event. Looking at the footage, Chappel saw a brief but discernible flash along the western portion of Jupiter's Southern Equatorial Belt, or SEB. Later that day, Chappel announced his discovery in a tweet: "Imaged Jupiter tonight. Looks awfully like an impact flash in the SEB." Chappel released a sharper version of the impact on Thursday, along with a colorized view of the apparent impact.

The flash appeared at at 4:07 a.m. UTC (12:07 a.m. ET) and lasted no longer than a second and a half, said astronomer Bob King in his coverage at Sky & Telescope. The impact still needs to be confirmed by other astronomers, but it certainly bears the hallmarks of a meteor strike, and not something that might be produced by Jupiter's lightning flashes or auroras. Looking at the flash, the size of the explosion seems small, but it's important to remember that Jupiter is the largest planet in the solar system. The meteor had to have been quite big to produce a flash of such prominence.

An anonymous reader quotes a report from the BBC: Increasingly frequent marine heatwaves can lead to the almost instant death of corals, scientists working on the Great Barrier Reef have found. These episodes of unusually high water temperatures are -- like heatwaves on land -- associated with climate change. Scientists studying coral after a heat event discovered that extreme temperature rises decayed reefs much more rapidly than previously thought. The study revealed that corals became up to 15% weaker after an extreme heat event, causing some fragments to actually break off from the reef. The study has been published in the journal Current Biology.

The Snazster writes: Dark matter remains one of the universe's greatest mysteries, with no one quite certain what it is or where it came from, even though it may comprise as much as 80% of the universe (if ignoring the still hypothetical dark energy). A recent study at John Hopkins University is now suggesting that it may be older than the Big Bang itself, which would actually help explain why our previous searches for it have failed thus far. Although this is not a new idea, this is the first time the possibility has been described with calculations that seem to support it. "Using a new, simple mathematical framework, the study shows that dark matter may have been produced before the Big Bang during an era known as the cosmic inflation when space was expanding very rapidly," reports ScienceDaily. "The rapid expansion is believed to lead to copious production of certain types of particles called scalars. So far, only one scalar particle has been discovered, the famous Higgs boson."

"The new study also suggests a way to test the origin of dark matter by observing the signatures dark matter leaves on the distribution of matter in the universe," the report adds. The study has been published in the journal Physical Review Letters.

An anonymous reader shares a report: Sudden shrieks of radio waves from deep space keep slamming into radio telescopes on Earth, spattering those instruments' detectors with confusing data. And now, astronomers are using artificial intelligence to pinpoint the source of the shrieks, in the hope of explaining what's sending them to Earth from -- researchers suspect -- billions of light-years across space. Usually, these weird, unexplained signals are detected only after the fact, when astronomers notice out-of-place spikes in their data -- sometimes years after the incident. The signals have complex, mysterious structures, patterns of peaks and valleys in radio waves that play out in just milliseconds. That's not the sort of signal astronomers expect to come from a simple explosion, or any other one of the standard events known to scatter spikes of electromagnetic energy across space.

Astronomers call these strange signals fast radio bursts (FRBs). Ever since the first one was uncovered in 2007, using data recorded in 2001, there's been an ongoing effort to pin down their source. But FRBs arrive at random times and places, and existing human technology and observation methods aren't well-primed to spot these signals. Now, in a paper published in the journal Monthly Notices of the Royal Astronomical Society, a team of astronomers wrote that they managed to detect five FRBs in real time using a single radio telescope. Wael Farah, a doctoral student at Swinburne University of Technology in Melbourne, Australia, developed a machine-learning system that recognized the signatures of FRBs as they arrived at the University of Sydney's Molonglo Radio Observatory, near Canberra.

Scientists have developed an "artificial tongue" that can differentiate a young whisky from an 18-year-old single malt. "The team, based in Scotland, say their device can be used to tell apart a host of single malts -- a move they say might help in the fight against counterfeit products," reports The Guardian. From the report: Writing in the journal Nanoscale, the team describe how their artificial tongue is based on a glass wafer featuring three separate arrays, each composed of 2 million tiny "artificial taste buds" -- squares about 500 times smaller than a human taste bud, with sides just 100nm long. There are six different types of these squares in the device, three types made from gold and three from aluminum. While one type of gold and one of aluminum are essentially bare, the surface of the other types are coated in different chemical substances.

Each of the three arrays contain one type of gold and one type of aluminum square. When light is shone on an array, it interacts with the electrons at the surface of the squares, resulting in dips in the reflected light which can be measured. These dips appear at slightly different wavelengths depending on which type of square the light interacts with. Crucially, these dips shift depending on the liquid surrounding the arrays. The upshot is that each liquid gives rise to its own "fingerprint" of measurements. That means the device can be used to tell apart different liquids -- and even identify them if they have been recorded before -- without revealing their makeup, rather like our own tongues do.